SUSTAINABILITY IN WINEMAKING: ROLE OF NON-SACCHAROMYCES YEASTS

LA SOSTENIBILITÀ IN VITICOLTURA PRIMA PARTE: UTILIZZO DI METSCHNIKOWIA PULCHERRIMA PER IL BIOCONTROLLO DEI VINI A BASSO CONTENUTO DI SOLFITi Sulla superficie dell'uva è presente un'ampia varietà di lieviti non Saccharomyces coinvolti nel processo di fermentazione spontanea. Questi lieviti sono spesso associati ad arresti di fermentazione e sono considerati lieviti deterioranti. Per il controllo di questi lieviti nella moderna enologia, viene ampiamente utilizzato come agente antimicrobico l'anidride solforosa (SO2), che grazie al suo basso costo e alla sua efficacia certificata è la migliore soluzione per controllare la crescita microbica. Negli ultimi anni l'attenzione si è concentrata sull'uso di lievito non-Saccharomyces come agente di biocontrollo per diminuire l'uso di (SO2). A questo proposito, l'uso di lieviti non-Saccharomyces nella fermentazione del vino potrebbe essere una strategia per ridurre l'uso di SO2 e allo stesso tempo migliorare il profilo aromatico del vino. Numerosi studi si sono concentrati sull'attività di biocontrollo di Metschnikowia pulcherrima. I risultati hanno mostrato che l'attività antimicrobica non sarebbe legata ad una proteina, come per il fattore killer, ma alla presenza di un precursore acido del pigmento responsabile della colorazione delle colonie. Alcuni studi hanno evidenziato che questa attività non influisce sulla crescita di S. cerevisiae ma ha mostrato un'inibizione nei confronti di lieviti deterioranti come Brettanomyces / Dekkera spp., Hanseniaspora spp. e Pichia spp. Parole chiave: Metschnikowia pulcherrima, vino, fermentazione sequenziale, anidride solforosa SECONDA PARTE: RIDUZIONE DEL CONTENUTO DI ETANOLO NEL VINO Negli ultimi decenni, l'aumento dell'etanolo nel vino, dovuto al cambiamento climatico globale e alle scelte dei consumatori, è una delle principali preoccupazioni nella vinificazione. Uno degli approcci più promettenti per ridurre il contenuto di etanolo nel vino è l'uso di lieviti non-Saccharomyces in co-fermentazione o fermentazione sequenziale con Saccharomyces cerevisiae. A questo proposito, valutiamo l'uso di Starmerella bombicola e S. cerevisiae in fermentazione sequenziale in condizioni di aerazione con l'obiettivo di ridurre il contenuto di etanolo con un prezioso profilo analitico. Dopo uno screening preliminare su mosto sintetico, sono state condotte prove di fermentazione al banco nel succo d'uva naturale valutando la condizione di aerazione (20 mL/L/min durante le prime 72 ore) sulla riduzione dell'etanolo e sul profilo analitico dei vini. I risultati hanno mostrato che S. bombicola/S. cerevisiae la fermentazione sequenziale in condizioni di aerazione ha determinato una riduzione di etanolo dell'1,46% (v/v) rispetto alla fermentazione pura di S. cerevisiae. Le condizioni di aerazione non hanno influenzato negativamente il profilo analitico della fermentazione sequenziale S. bombicola/S. cerevisiae in particolare una sovrapproduzione di acidità volatile e acetato di etile. D'altra parte, queste condizioni hanno migliorato notevolmente la produzione di glicerolo e acido succinico che influiscono positivamente sulla struttura e sul corpo del vino.SUSTAINABILITY IN WINEMAKING FIRST PART: USE OF METSCHNIKOWIA PULCHERRIMA FOR THE BIOCONTROL OF WINES WITH LOW SULPHITES A wide variety of non-Saccharomyces yeast are present on the grape surface and involved in spontaneous fermentation process. These yeasts are often associated with stuck fermentations and are considered spoilage yeasts. To control these yeasts in modern oenology, sulfur dioxide (SO2) is widely used as an antimicrobial agent, which thanks to its low cost and certified effectiveness is the best solution to control microbial growth. During the last few years the attention was focused on the use of non-Saccharomyces yeast as biocontrol agent to decrease the use of (SO2). In this regard, the use of non-Saccharomyces yeasts in wine fermentation could be a strategy to reduce the use of SO2 and at the same time improve the aroma profile of wine. Numerous studies focused on bio-control activity of Metschnikowia pulcherrima. The results showed that the antimicrobial activity would not be linked to a protein, as for the killer factor, but to the presence of an acid precursor of the pigment responsible of coloration of the colonies. Some studies highlighted that this activity don’t affect the growth of S. cerevisiae but showed an inhibition against spoilage yeasts such as Brettanomyces / Dekkera spp., Hanseniaspora spp., and Pichia spp . In this work, the use of M. pulcherrima and S. cerevisiae in sequential fermentations was evaluated to produce wines with low sulphite content, analytically correct and having a characteristic aromatic bouquet. The fermentation trials were carried out in cellar using Verdicchio grape juice. The tanks were inoculated with M. pulcherrima for the first 48 hours. After 48 hours of fermentation, the S. cerevisiae strain was inoculated to complete the fermentation. The results showed that in the absence of added SO2, the concentration of indigenous microorganisms was significantly reduced when compared with the control thesis without inoculation of M. pulcherrima. In conclusion, the use of M. pulcherrima in sequential fermentation with S.cerevisiae is a suitable strategy to obtain wines with a low SO2 content while maintaining a high quality level. Keywords: Metschnikowia pulcherrima, wine, sequential fermentation, sulfure dioxide SECOND PART: REDUCTION OF ETHANOL CONTENT IN WINE In the last few decades, the increase of ethanol in wine, due to global climate change and consumers choice is one of the main concerns in winemaking. One of the most promising approaches in reducing the ethanol content in wine is the use of non-Saccharomyces yeasts in co-fermentation or sequential fermentation with Saccharomyces cerevisiae. In this regard, we evaluate the use of Starmerella bombicola and S. cerevisiae in sequential fermentation under aeration condition with the aim of reducing the ethanol content with valuable analytical profile. After a preliminary screening in synthetic grape juice, bench-top fermentation trials were conducted in natural grape juice by evaluating the aeration condition (20 mL/L/min during the first 72 h) on ethanol reduction and on the analytical profile of wines. The results showed that S. bombicola/S. cerevisiae sequential fermentation under aeration condition determined an ethanol reduction of 1.46% (v/v) compared with S. cerevisiae pure fermentation. Aeration condition did not negatively affect the analytical profile of sequential fermentation S. bombicola/S. cerevisiae particularly an overproduction of volatile acidity and ethyl acetate. On the other hand, these conditions strongly improved the production of glycerol and succinic acid that positively affect the structure and body of wine

Nanoparticle devices for brain-inspired computing.

The race towards smarter and more efficient computers is at the core of our technology industry and is driven by the rise of more and more complex computational tasks. However, due to limitations such as the increasing costs and inability to indefinitely keep shrinking conventional computer chips, novel hardware architectures are needed. Brain-inspired, or neuromorphic, hardware has attracted great interest over the last decades. The human brain can easily carry out a multitude of tasks such as pattern recognition, classification, abstraction, and motor control with high efficiency and extremely low power consumption. Therefore, it seems logical to take inspiration from the brain to develop new systems and hardware that can perform interesting computational tasks faster and more efficiently. Devices based on percolating nanoparticle networks (PNNs) have shown many features that are promising for the creation of low-power neuromorphic systems. PNN devices exhibit many emergent brain-like properties and complex electrical activity under stimulation. However, so far PNNs have been studied using simple two-contact devices and relatively slow measuring systems. This limits the capabilities of PNNs for computing applications and questions such as whether the brain-like properties continue to be observed at faster timescales, or what are the limits for operation of PNN devices remain unanswered. This thesis explores the design, fabrication, and testing of the first successful multi- contact PNN devices. A novel and simple fabrication technique for the creation of working electrical contacts to nanoparticle networks is presented. Extensive testing of the multi-contact PNN devices demonstrated that electrical stimulation of multiple input contacts leads to complex switching activity. Complex switching activity exhibited different patterns of switching behaviour with events occurring on all contacts, on few contacts, or only on a single contact. The device behaviour is investigated for the first time at microsecond timescales, and it is found that the PNNs exhibit stochastic spiking behaviour that originates in single tunnel gaps and is strikingly similar to that observed in biological neurons. The stochastic spiking behaviour of PNNs is then used for the generation of high quality random numbers which are fundamental for encryption and security. Together the results presented in this thesis pave the way for the use of PNNs for brain-inspired computing and secure information processing

Chitosan-based scaffold modified with D-(+) raffinose for cartilage repair: an in vivo study

BackgroundOsteochondral defects significantly affect patients¿ quality of life and represent challenging tissue lesions, because of the poor regenerative capacity of cartilage. Tissue engineering has long sought to promote cartilage repair, by employing artificial scaffolds to enhance cell capacity to deposit new cartilage. An ideal biomaterial should closely mimic the natural environment of the tissue, to promote scaffold colonization, cell differentiation and the maintenance of a differentiated cellular phenotype. The present study evaluated chitosan scaffolds enriched with D-(+) raffinose in osteochondral defects in rabbits. Cartilage defects were created in distal femurs, both on the condyle and on the trochlea, and were left untreated or received a chitosan scaffold. The animals were sacrificed after 2 or 4 weeks, and samples were analysed microscopically.ResultsThe retrieved implants were surrounded by a fibrous capsule and contained a noticeable inflammatory infiltrate. No hyaline cartilage was formed in the defects. Although defect closure reached approximately 100% in the control group after 4 weeks, defects did not completely heal when filled with chitosan. In these samples, the lesion contained granulation tissue at 2 weeks, which was then replaced by fibrous connective tissue by week 4. Noteworthy, chitosan never appeared to be integrated in the surrounding cartilage.ConclusionsIn conclusion, the present study highlights the limits of D-(+) raffinose-enriched chitosan for cartilage regeneration and offers useful information for further development of this material for tissue repair

Type-B monoamine oxidase inhibitors in neurological diseases: clinical applications based on preclinical findings

Type-B monoamine oxidase inhibitors, encompassing selegiline, rasagiline, and safinamide, are available to treat Parkinson's disease. These drugs ameliorate motor symptoms and improve motor fluctuation in the advanced stages of the disease. There is also evidence supporting the benefit of type-B monoamine oxidase inhibitors on non-motor symptoms of Parkinson's disease, such as mood deflection, cognitive impairment, sleep disturbances, and fatigue. Preclinical studies indicate that type-B monoamine oxidase inhibitors hold a strong neuroprotective potential in Parkinson's disease and other neurodegenerative diseases for reducing oxidative stress and stimulating the production and release of neurotrophic factors, particularly glial cell line-derived neurotrophic factor, which support dopaminergic neurons. Besides, safinamide may interfere with neurodegenerative mechanisms, counteracting excessive glutamate overdrive in basal ganglia motor circuit and reducing death from excitotoxicity. Due to the dual mechanism of action, the new generation of type-B monoamine oxidase inhibitors, including safinamide, is gaining interest in other neurological pathologies, and many supporting preclinical studies are now available. The potential fields of application concern epilepsy, Duchenne muscular dystrophy, multiple sclerosis, and above all, ischemic brain injury. The purpose of this review is to investigate the preclinical and clinical pharmacology of selegiline, rasagiline, and safinamide in Parkinson's disease and beyond, focusing on possible future therapeutic applications

Aptamer-Mediated Selective Protein Affinity to Improve Scaffold Biocompatibility

Protein adsorption on surfaces occurs shortly after scaffold insertion. This process is of pivotal importance to achieve therapeutic success in tissue engineering (TE), and favorable proteins should be adsorbed at the interface without unfolding to preserve their structure and function. Protein misfolding at the interface is a common phenomenon, which can impair cell adhesion and scaffold colonization. Many efforts have been done to improve scaffold biocompatibility by ameliorating protein adsorption, but with poor results. In the present chapter, we propose the use of a novel class of molecules, aptamers, to improve scaffold biocompatibility. Aptamers are small, single stranded oligonucleotides, which specifically bind to a target molecule: they work as antibodies, but without many of the drawbacks associated to the use of antibodies. We propose to immobilize aptamers on scaffolds to retain specific proteins, acting as docking points to guide cell activity. In particular, we show the results obtained by enriching different polymeric scaffolds with aptamers against human fibronectin, a naturally abundant protein in tissues, which plays a pivotal role in cell adhesion. We demonstrate that scaffold enrichment with aptamers lead to a better colonization of the substrate from cells. The results we obtained pave the way to the possibility of further investigating the role of aptamers as useful molecules to improve scaffold biocompatibility in the contest of tissue engineering

Age at Onset Influences Progression of Motor and Non-Motor Symptoms during the Early Stage of Parkinson’s Disease: A Monocentric Retrospective Study

The interactions between the age at onset with other pathogenic mechanisms and the interplays between the disease progression and the aging processes in Parkinson’s disease (PD) remain undefined, particularly during the first years of illness. Here, we retrospectively investigated the clinical presentation and evolution of the motor and non-motor symptoms and treatment-related complications during the first 5 years of illness in subjects categorized according to age at onset. A total of 131 subjects were divided into “Early-Onset-PD” (EOPD; onset ≤49 years), “Middle-Onset-PD” (MOPD; onset 50–69 years) and “Late-Onset-PD” (LOPD; onset ≥70 years). The T0 visit was set at the time of the clinical diagnosis; the T1 visit was 5 years (±5 months) later. At T0, there were no significant differences in the motor features among the groups. At T1, the LOPD patients displayed a significantly higher frequency of gait disturbances and a higher frequency of postural instability. Moreover, at T1, the LOPD subjects reported a significantly higher frequency of non-motor symptoms; in particular, cardiovascular, cognitive and neuropsychiatric domains. The presented results showed a significantly different progression of motor and non-motor symptoms in the early course of PD according to the age at onset. These findings contribute to the definition of the role of age at onset on disease progression and may be useful for the pharmacological and non-pharmacological management of PD

Four Days Are Enough to Provide a Reliable Daily Step Count in Mild to Moderate Parkinson’s Disease through a Commercial Smartwatch

Daily steps could be a valuable indicator of real-world ambulation in Parkinson’s disease (PD). Nonetheless, no study to date has investigated the minimum number of days required to reliably estimate the average daily steps through commercial smartwatches in people with PD. Fifty-six patients were monitored through a commercial smartwatch for 5 consecutive days. The total daily steps for each day was recorded and the average daily steps was calculated as well as the working and weekend days average steps. The intraclass correlation coefficient (ICC) (3,k), standard error of measurement (SEM), Bland–Altman statistics, and minimum detectable change (MDC) were used to evaluate the reliability of the step count for every combination of 2–5 days. The threshold for acceptability was set at an ICC ≥ 0.8 with a lower bound of CI 95% ≥ 0.75 and a SAM < 10%. ANOVA and Mann–Whitney tests were used to compare steps across the days and between the working and weekend days, respectively. Four days were needed to achieve an acceptable reliability (ICC range: 0.84–0.90; SAM range: 7.8–9.4%). In addition, daily steps did not significantly differ across the days and between the working and weekend days. These findings could support the use of step count as a walking activity index and could be relevant to developing monitoring, preventive, and rehabilitation strategies for people with PD

Bilateral Symmetry of Visual Function Loss in Cone-Rod Dystrophies.

PURPOSE: To investigate bilateral symmetry of visual impairment in cone-rod dystrophy (CRD) patients and understand the feasibility of clinical trial designs treating one eye and using the untreated eye as an internal control. METHODS: This was a retrospective study of visual function loss measures in 436 CRD patients followed at the Ophthalmology Department of the Catholic University in Rome. Clinical measures considered were best-corrected visual acuity, focal macular cone electroretinogram (fERG), and Ganzfeld cone-mediated and rod-mediated electroretinograms. Interocular agreement in each of these clinical indexes was assessed by t- and Wilcoxon tests for paired samples, structural (Deming) regression analysis, and intraclass correlation. Baseline and follow-up measures were analyzed. A separate analysis was performed on the subset of 61 CRD patients carrying likely disease-causing mutations in the ABCA4 gene. RESULTS: Statistical tests show a very high degree of bilateral symmetry in the extent and progression of visual impairment in the fellow eyes of CRD patients. CONCLUSIONS: These data contribute to a better understanding of CRDs and support the feasibility of clinical trial designs involving unilateral eye treatment with the use of fellow eye as internal control

B cell depletion attenuates CD27 signaling of T helper cells in multiple sclerosis

Multiple sclerosis is a chronic inflammatory disease of the central nervous system. Whereas T cells are likely the main drivers of disease development, the striking efficacy of B cell-depleting therapies (BCDTs) underscore B cells' involvement in disease progression. How B cells contribute to multiple sclerosis (MS) pathogenesis-and consequently the precise mechanism of action of BCDTs-remains elusive. Here, we analyze the impact of BCDTs on the immune landscape in patients with MS using high-dimensional single-cell immunophenotyping. Algorithm-guided analysis reveals a decrease in circulating T follicular helper-like (Tfh-like) cells alongside increases in CD27 expression in memory T helper cells and Tfh-like cells. Elevated CD27 indicates disrupted CD27/CD70 signaling, as sustained CD27 activation in T cells leads to its cleavage. Immunohistological analysis shows CD70-expressing B cells at MS lesion sites. These results suggest that the efficacy of BCDTs may partly hinge upon the disruption of Th cell and B cell interactions